/// <summary>
/// Allows each screen to run logic.
/// </summary>
public override void Update(GameTime gameTime)
{
// Read the keyboard and gamepad.
input.Update();
// Make a copy of the master screen list, to avoid confusion if
// the process of updating one screen adds or removes others
// (or it happens on another thread)
screensToUpdate.Clear();
foreach (GameScreenBase screen in screens)
{
screensToUpdate.Add(screen);
}
bool otherScreenHasFocus = !Game.IsActive;
bool coveredByOtherScreen = false;
// Loop as long as there are screens waiting to be updated.
while (screensToUpdate.Count > 0)
{
// Pop the topmost screen off the waiting list.
GameScreenBase screen = screensToUpdate[screensToUpdate.Count - 1];
screensToUpdate.RemoveAt(screensToUpdate.Count - 1);
// Update the screen.
screen.Update(gameTime, otherScreenHasFocus, coveredByOtherScreen);
if (screen.ScreenState == ScreenState.TransitionOn || screen.ScreenState == ScreenState.Active)
{
// If this is the first active screen we came across,
// give it a chance to handle input and update presence.
if (!otherScreenHasFocus)
{
screen.HandleInput(input);
screen.UpdatePresence(); // presence support
otherScreenHasFocus = true;
}
// If this is an active non-popup, inform any subsequent
// screens that they are covered by it.
if (!screen.IsPopup)
{
coveredByOtherScreen = true;
}
}
}
// Print debug trace?
if (traceEnabled)
{
TraceScreens();
}
}
/// <summary>
/// Removes a screen from the screen manager. You should normally
/// use GameScreen.ExitScreen instead of calling this directly, so
/// the screen can gradually transition off rather than just being
/// instantly removed.
/// </summary>
public void RemoveScreen(GameScreenBase screen)
{
// If we have a graphics device, tell the screen to unload content.
if ((graphicsDeviceService != null) &&
(graphicsDeviceService.GraphicsDevice != null))
{
screen.UnloadContent();
}
screens.Remove(screen);
screensToUpdate.Remove(screen);
}
/// <summary>
/// Adds a new screen to the screen manager.
/// </summary>
public void AddScreen(GameScreenBase screen)
{
screen.ScreenManager = this;
// If we have a graphics device, tell the screen to load content.
if ((graphicsDeviceService != null) && (graphicsDeviceService.GraphicsDevice != null))
{
screen.LoadContent();
}
screens.Add(screen);
}
/// <summary>
/// Removes a screen from the screen manager. You should normally
/// use GameScreen.ExitScreen instead of calling this directly, so
/// the screen can gradually transition off rather than just being
/// instantly removed.
/// </summary>
public void RemoveScreen( GameScreenBase screen )
{
// If we have a graphics device, tell the screen to unload content.
if ( ( graphicsDeviceService != null ) &&
( graphicsDeviceService.GraphicsDevice != null ) )
{
screen.UnloadContent();
}
screens.Remove( screen );
screensToUpdate.Remove( screen );
}
/// <summary>
/// Adds a new screen to the screen manager.
/// </summary>
public void AddScreen( GameScreenBase screen )
{
screen.ScreenManager = this;
// If we have a graphics device, tell the screen to load content.
if ( ( graphicsDeviceService != null ) && ( graphicsDeviceService.GraphicsDevice != null ) )
{
screen.LoadContent();
}
screens.Add( screen );
}
